Pressure Online

Special Report from the Safety Committee

RISK MANAGEMENT AND THE USE OF HYPERBARIC OXYGEN CHAMBERS

TOM WORKMAN and JIM BELL, UHMS Safety Committee

Over the past four decades we have seen a geometric growth in the number of clinical hyperbaric medicine facilities. The numbers have grown, from approximately 27 facilities in the early 1970s to now more than 1,350 hospital-based programs. There is no reliable estimate of the number of non-hospital based facilities in operation. For the most part, facilities that are a part of a healthcare system are well regulated; those in non-healthcare rated occupancies, such as health spas, commercial office buildings and homes, much less so.

Areas of concern

A segment of the community that presents the highest level of concern is based on the use of portable, fabric, low-pressure hyperbaric chambers that do not meet existing safety codes such as the National Fire Protection Association (NFPA) 99, Health Care Facilities Code. These types of chambers, while cleared by the FDA as a Class II medical device,do not comply with American Society of Mechanical Engineers, Pressure Vessels for Human Occupancy -1 (ASME PVHO-1) hyperbaric chamber design and fabrication code (as required by NFPA 99) nor with the installation and operational requirements mandated in NFPA 99.

A confounding problem is that local authorities having jurisdiction (AHJs) are not aware that these devices are being used in their jurisdiction. When a traditional hyperbaric chamber is installed, installation permits, and other paperwork are required, and accordingly, AHJs are appropriately notified. There is no comparable notification process for these low-pressure chambers, as they are delivered by a commercial carrier (such as FedEx) and require no traditional installation. Plus, they can be operational within 15-30 minutes of receipt. Because of this, there is no mechanism to notify the AHJ of their presence, and thus they routinely operate “under the radar” of the established regulatory community. There are estimated to be more than 10,000 such hyperbaric chambers in use throughout the country.

Additional examples of non-compliance . . .

Other examples of non-compliance to NFPA 99 are numerous. For example, NFPA 99 requires that the exhaust from a hyperbaric chamber be piped to the exterior of the building housing the chamber. These low-pressure chambers, however, vent to the ambient space in the room in which they are located.

Perhaps the most concerning risk is that these chambers are frequently used with oxygen concentrators to increase the concentration of oxygen that the patient breathes while in the chamber. When used in this configuration, the concentration of oxygen inside the chamber often exceeds the NFPA 99 limit of 23.5%. Operation of hyperbaric chambers with atmospheres containing more than 23.5% oxygen requires the patient to be grounded. Patients treated in these portable chambers are rarely, if ever, electrically grounded. This is exacerbated by facility operators who encourage or allow patients to take into the chamber with them their tablet, cell phone, laptop, and similar devices. The use of these types of electrical devices in a hyperbaric chamber is strictly prohibited by NAPA 99.

. . . and a recent example

The death of a young autistic boy from North Carolina (June 9, 2011) might have been avoided had these low-pressure chambers been regulated as required. As noted above, they do not comply with the well-established design and fabrication code, ASME PVHO-1, Safety Standard for Pressure Vessels for Human Occupancy. North Carolina mandates compliance to this code. NFPA 99 mandates compliance to this code. The Life Safety Code (NFPA 101) invokes compliance to the hyperbaric requirements noted in NFPA 99, which also mandates compliance through reference. Therefore, if properly regulated, hyperbaric chambers of this type would not have been allowed to operate in North Carolina.

The National Fire Protection Association recently highlighted the importance of this issue in the January/February issue of its magazine, NFPA Journal. The story, entitled “The Air In There,” provides a general overview of the hazards and challenges associated with hyperbaric chambers and informs local authorities having jurisdiction about the magnitude of the problem while offering suggestions on how to deal with it.

“This is an area of health care that a lot of AHJs may not know that much about,” said Scott Sutherland, executive editor of NFPA Journal. “With these types of facilities proliferating, though, it’s important for AHJs to understand the potential hazards. I think our story does a good job of describing those hazards and of explaining why this is an area of concern right now.”

It's a growing concern

A casual search of the internet demonstrates the prolific use of low- pressure fabric chambers for indications that have not been proven. At the time of the posting the FDA had received 27 complaints from consumers over three years about treatment centers promoting hyperbaric chambers for uses not cleared by the agency.

Low-pressure fabric chambers are designed and have an FDA 510(K) premarket notification to be pressurized with air to treat acute mountain sickness. They are not built to ASME PVHO or NFPA 99 codes. However, they are routinely being operated outside of the FDA approval and NFPA codes and standards. The use of these chambers is sometimes referred to as mild hyperbaric oxygen therapy (mHBOT).

From a position of risk management we do not support the use of low-pressure portable fabric chambers for anything other than acute mountain sickness. Clinical hyperbaric oxygen therapy as defined by the Undersea and Hyperbaric Medical Society, Hyperbaric Oxygen Therapy Indications, 13th edition, requires that the patient breathe near 100% oxygen while inside a chamber pressurized to at least 1.5 atmospheres absolute. The low-pressure fabric chambers are not designed to provide this clinical dose of oxygen and pressure. Clinical hyperbaric oxygen chambers need to be designed, manufactured, housed and operated according to the FDA, NFPA and ASME-PVHO codes.